sequential waits -- how to proceed

Oracle ver is 9.2 running on EMC array. I am executing a pl/sql
procedure which does an update on a fact table. There is an unique
index on the fact, with clearly shows up in the explain plan for
udapte.
I ran 10046 event for a 18 min duration during this update process and
then killed it.
On doing a tkprof on the trace file with waits set to Y, i get

As you can see the wait on db file sequential read is 935 ...i am
thinking it is in sec or is it centisec ??
i can see a degradation of perf as time continues. After 10 min , the
number of rows updated stays at 150 rows/sec which is pretty bad.
I have figured out the db file, table and block by looking into p1,p2.
That table is partioned and all the partitions are present on the same
tbs. It has 2 -- 8 gb files and p1 consistently points to either of the 2
data files.
I would like your help in trying to find out how to proceed from here ?.
I am stuck.
Ohter than moving the data files aound to different file systems ans
spreading them around, is there anything else thaty i can do to figure
out this problem.

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Received on Tue Jun 17 2003 - 17:48:48 CDT